So why did he kiss her *now*?
Let's think on it.
She's depressed, upset, angry with him, incredibly vulnerable, House stares at her and realises in that moment that the reason he's been such an utter, utter bastard to her is because he is in love with her. Y/N? It took him long enough, but I guess that makes some sense, although it's a little disturbing that he has to see Cuddy at her absolute lowest before he -- for all intents and purposes -- takes advantage of her.
It's a good thing then that he left when he did, and if the show does decide to go down the House/Cuddy route, I hope it's more on the funny, sexy end of the scale, less on the disturbing, woman-bashing end of it.
All that said, I found the kiss totally hot.
I have now seen the first three episodes of "Summer Heights High" and I can officially say that I absolutely hate it. I laughed at the characters in the first episode but soon discovered that they are one dimensional caricatures with no redeeming features, and at that point I stopped laughing. The misanthropy on display in this show makes it an unbearable viewing experience for someone like me, but if you enjoy shows with no sympathetic characters but genuinely edgy -- and often clever -- satire, this might appeal to you.